Disk player

ABSTRACT

A disc player  10  is equipped with a positioning unit  14  that has step plate  54  and positions a disc  1 , a clamper unit  15  that has a clamp plate  66  and carries out a clamp operation on the disc positioned by the positioning unit, a drive unit  16  that has a pickup and a turntable  19  on a drive plate  18 , and rotates the disc clamped on the turntable by the clamper unit to take information from the disc by the pickup, wherein the positioning unit and the clamper unit are provided separately from each other, and movable vertically to the drive unit.

TECHNICAL FIELD

[0001] The present invention relates to a disc player that is mounted ina vehicle and reproduces information in a recording medium disc such asCD (compact disc) or the like.

[0002] There is known a conventional disc player such as a CD player orthe like which is mounted in a vehicle and designed such that a clamperfor guiding and positioning a disc to a predetermined position andclamping the disc onto a turntable is equipped to a drive plate on whicha pickup and the turntable are disposed so that the clamper can carryout the above operation by rotation of a clamp arm.

[0003] However, in such a disc player, the rotation amount (rotationangle) of the clamp arm rotating within a range in the height directionof the disc player must be increased to move the disc in the verticaldirection to the drive plate by a predetermined amount. Therefore, ithas been difficult to reduce the thickness of the disc player.

[0004] An object of the present invention has been implemented inconsideration of the above circumstances, and is to provide a discplayer that can be designed to be small in thickness.

SUMMARY OF THE INVENTION

[0005] According to the present invention, a disc player comprises apositioning unit for positioning a disc, a clamper unit for performing aclamp operation on the disc positioned by the positioning unit, and adrive unit that has a pickup and a turntable and rotates the discclamped on the turntable by the clamp unit to take out information fromthe disc by the pickup, wherein the positioning unit and the clamperunit are provided separately from each other and movable substantiallyvertically to the drive unit.

[0006] Further, in the above invention, a step plate equipped to thepositioning unit and a clamp plate equipped to the clamper unit areengaged with a cam groove of a cam plate movable in parallel to a driveplate equipped to the drive unit, and movable vertically to the driveplate by movement of the cam plate.

[0007] In the above invention, the step plate and the clamp plate aremoved synchronously and vertically to the drive plate by the movement ofthe cam plate.

[0008] In the above invention, fit members which are provided to thestep plate and the clamp plate and engaged with said cam grooves of saidcam plate are fit pawls that are integrally formed by bending anderecting.

[0009] In the above invention, the fit pawls of the step plate and theclamp plate are integrally formed by bending and erecting in a formingprocess thereof.

[0010] In the above invention, the positioning unit is designed so as toposition plural kinds of discs that are different in size.

[0011] In the above invention, the positioning unit has a step plate, aG plate which is freely rotatably provided to the step plate and has, atone end thereof, a disc stopper on which a disc can be supported, and asensor arm having, at one end thereof, an arm rod that can be fitted tothe disc, the fitting positions of the other ends of the G plate and thesensor arm being changeable in accordance with plural discs different indiameter so that the discs can be positioned.

[0012] In the above invention, the moving amounts of the positioningunit and the clamper unit are set to different values.

[0013] In the above invention, the moving amount of the clamper unit isset to a value larger than that of the positioning unit.

[0014] In the above invention, the moving amount of the positioning unitis set so that a vibration-isolation stroke can be kept, and the movingamount of the clamper unit is set so that the vibration-isolation strokecan be kept and the clearance between the clamper unit and the clamperring for clamping the disc onto the turntable can be kept.

[0015] According to the present invention, the step plate and the clampplate are designed so as to be movable vertically to the drive plate, sothat the moving amounts of the step plate and the clamp plate can bemore reduced as compared with a case where the clamper for clamping thedisc onto the turntable is moved relatively to the turntable by therotation of the clamp arm and a case where the step plate and the clampplate are integrally rotated, and thus the disc player can be designedin a thin structure.

[0016] According to the present invention, the step plate and the clampplate are separately provided, and thus the moving amounts of both theplates can be set to different values. That is, the moving amount of thestep plate can be set to such a value that a vibration-isolation strokecan be kept, and the moving amount of the clamp plate can be set to sucha value that the vibration-isolation can be kept, and also the clearancebetween the clamp plate and the clamper ring can be kept.

[0017] Further, according to the present invention, the fit memberswhich are provided to the step plate and the clamp plate and engageablewith the cam grooves of the cam plate are fitting pawls which areintegrally formed by bending and erecting them. Therefore, as comparedwith the construction that the fitting members comprise caulking pins,the structure of the step plate and the clamp plate can be moresimplified, and thus the structure of the disc player can be moresimplified.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1A shows an embodiment of a disc player according to thepresent invention, and is a plan view showing the initial state of thedisc player when a disc stopper is located at an initial position, and

[0019]FIG. 1B is a plan view showing a trigger rack, an S arm stopper,etc. of FIG. 1A.

[0020]FIG. 2A is a plan view showing a disc positioning state of thedisc player when the disc stopper is located at a disc positioningposition in the disc player of FIG. 1A, and

[0021]FIG. 2B is a plan view showing a trigger rack, an S arm stopper,etc. of FIG. 2A.

[0022]FIG. 3A is a plan view showing a disc chucking state of the discplayer when the disc stopper is located at the disc positioning positionin the disc player of FIG. 1A, and

[0023]FIG. 3B is a plan view showing a trigger rack, an S arm stopper,etc. of FIG. 3A.

[0024]FIG. 4A is a plan view showing a centering-completed state of thedisc player when the disc stopper is located at a retracting position inthe disc player of FIG. 1A, and

[0025]FIG. 4B is a plan view showing a trigger rack, an S arm stopper,etc. of FIG. 4A.

[0026]FIGS. 5A, 5B and 5C are cross-sectional views of the step plateand the clamp plate which are taken along the center lines of FIGS. 2A,3A, 4A.

[0027]FIG. 6 is a back view showing the player main body of the discplayer of FIG. 1A.

[0028]FIG. 7 is a perspective view showing the step plate and the clampplate of FIG. 1A.

[0029]FIGS. 8A and 8B are perspective views showing an R cam plate andan L cam plate of FIGS. 1B to 5A.

[0030]FIG. 9A to 9D are diagrams showing a lock releasing operation in alock mechanism of the R cam plate of FIG. 6.

PREFERRED EMBODIMENTS OF THE INVENTION

[0031] Preferred embodiments according to the present invention will bedescribed hereunder with reference to the accompanying drawings.

[0032] A disc player shown in FIG. 1A is used to reproduce informationrecorded on a recording medium disc 1 such as a CD (compact disc), DVD(digital versatile disc) or the like, and it comprises a player mainbody 11 and a chassis unit 12. Further, as shown in FIG. 5A, the playermain body 11 comprises a loading unit 13, a positioning unit 14, aclamper unit 15 and a drive unit 16.

[0033] The chassis unit 12 is equipped with a vibration-isolatingstructure having a clamper and a spring (not shown) on a chassis 17thereof, and the player main body 11 is supported through thevibration-isolating structure by the chassis 17 so as to be floated

[0034] As shown in FIGS. 5A and 6, in a drive unit 16 of the player mainbody 11, a turntable 19 is disposed at the center on the surface of adrive plate 18 while a spindle motor 20 is disposed at the center of theback surface, and the spindle motor 20 rotates the turntable 19.Further, a pickup (not shown) is mounted on the drive plate 18, andtakes out information from the disc 1 which is clamped on the turntableas described later and rotated.

[0035] Further, side walls 21 are integrally formed at both the rightand left sides of the drive unit 16, and longitudinal grooves 22 (FIG.5A) extending in the up-and-down direction (in the vertical direction tothe drive plate 18) are formed on the side walls 21. An upper plate 23(FIG. 1A) is fixedly disposed at the front portion of the drive unit 16,and a disc sensor 24 for detecting the disc inserted by a user issecured to the upper plate 23.

[0036] As shown in FIGS. 5A to 5C and 6, an R cam plate 25R and an L camplate 25L are disposed on both the side walls 21 of the drive unit 16 soas to be movable in parallel to the drive plate 18 in the frontward andbackward directions of the disc player 10. As shown in FIGS. 5A to 5Cand FIGS. 8A and 8B, cam grooves 26A, 26B and 26C are obliquely formedin the R cam plate 25R and the L cam plate 25L.

[0037] The R cam plate 25R and the L cam plate 25L are linked to eachother by a cranked crank shaft 27 and a loading plate (described later).The forward and backward movement of the R cam plate 25R is transferredto the L cam plate 25L by the crank shaft 27, and the L cam plate 25Land the R cam plate 25R are movable in synchronism with each other.

[0038] As shown in FIG. 6, a loading motor 28, a gar wheel sequence 29and a trigger rack 30 are disposed at the R cam plate 25R side on theback surface of the drive plate 18. Further, an S arm stopper 40 isdisposed at the position corresponding to the trigger rack 30 on thesurface of the drive plate 18.

[0039] The trigger rack 30 is disposed so as to be movable in theforward and backward directions of the disc player 10, and it is urgedbackwardly at all times by a tensile coil spring suspended between thetrigger rack 30 and the drive plate 18. As shown in FIGS. 9A to 9D, thetrigger rack 30 has a trigger groove 42 oblique to the above movingdirections and a rack 43. A pin 40A (FIG. 1B) implanted in the driveunit 16 is inserted in the elongated hole of the S arm stopper 40, sothat the S arm stopper 40 is movable in the forward and backwarddirections of the disc player 10 and also rotatable. Further, the S armstopper 40 is equipped with a lock pin 44.

[0040] The gear wheel sequence shown in FIG. 6 comprises a first gear 31coupled to the shaft of the loading motor 28, a second gear 32 engagedwith the first gear 31, a third gear 33, a fourth gear 34, a fifth gear35, a sixth gear 36 and a seventh gear 37 which are mutually engagedwith one another, and an idle gear 38 and a final gear 39 which aremutually engaged with each other. The second gear 32 is engaged with thethird gear 33 and the idle gear 38.

[0041] The seventh gear 37 is coupled to a loading roller 41 asdescribed later. The final gear 39 is engageable with the rack 43 of thetrigger rack 30 and the rack 45 of the R cam plate 25R as shown in FIGS.6 and 9A to 9D. The rack 45 is formed in a driving piece 46 extending tothe back surface side of the drive plate 18 in the R cam plate 25R.

[0042] The rack 45 of the R cam plate 25R is prevented from beingunnecessarily engaged with the final gear 39 by the lock operation ofthe lock mechanism 47.

[0043] That is, as shown in FIG. 9A, the lock mechanism 47 has akey-shaped hole 48 formed in the drive plate 18, an elongated holeformed in the driving piece 46 of the R cam plate 25R, the triggergroove 42 of the trigger rack 30 described above, and a lock pin 44 ofthe S arm stopper 40. The key-shaped hole 48 has a first hole 51extending in the forward and backward directions of the drive plate 18,and a second hole 52 perpendicular to the first hole 51. The elongatedhole 49 extends in parallel to the second hole 52. The lock pin 44 isfitted in the key-shaped hole 48, the elongated hole 49 and the triggergroove 42.

[0044] Under the state that the disc 1 is not inserted in the play mainbody 11 of the disc player 10, the lock pin 44 is fitted in the secondhole 52 of the key-shaped hole as shown in FIG. 9A, so that the R camplate 25R is prevented from moving in the forward and backwarddirections of the disc player 10. Accordingly, even when a carelessshock such as falling impact or the like is applied to the player mainbody 11, the final gear 39 is prevented from being engaged with the rack45 of the R cam plate 25R.

[0045] The release of the lock operation of the lock mechanism 47described above is carried out as follows.

[0046] That is, when the trigger rack 30 is pressed in the forwarddirection of the disc player 10 by a sensor arm 57 described later andforwardly moved against the urging force of the tensile coil spring 30A,the rack 43 of the trigger rack 30 is engaged with the final gear 39,and the trigger rack 30 is further moved in the forward direction of thedisc player 10 by the driving force of the loading motor 28 as shown inFIG. 9B. At this time, the trigger groove 42 of the trigger rack 30moves the lock pin 44 from the second hole 52 of the key-shaped hole 48to the first hole 51, whereby the lock operation of the lock mechanism47 is released. Thereafter, when the trigger rack 30 further presses theR cam plate 25R through the lock pin 44, the rack 45 of the R cam plate25R is engaged with the final gear 39 as shown in FIG. 9C and the R camplate 25R is moved in the forward direction of the disc player 10 (FIG.9D). At this time, the lock pin 44 is moved in the first hole 51 of thekey-shaped hole 48.

[0047] As shown in FIGS. 5A to 5C and 6, the loading unit 13 comprisesthe loading roller 41 and a loading plate (not shown). The loading plateis rotatably supported on the upper plate 23 (FIG. 1A), and the shaft ofthe loading roller 41 is supported by the loading plate so as to befreely rotatable. The shaft of the loading roller 41 is fitted in thecam groove 26A of the R cam plate 25R at one end thereof, and fitted inthe elongated hole formed in the side wall 21 of the drive plate 18 atthe other end thereof.

[0048] The loading plate presses the loading roller 41 against the discloader 41 by spring force. The driving force of the loading motor ofFIG. 6 is transferred to the loading roller 41 through the first gear 31to the seventh gear 37 of the gear wheel sequence. Accordingly, when thedisc sensor 24 detects the disc 1 and the loading motor 28 is actuated,the loading roller 41 is rotated to draw and feed the disc 1 into theplayer main body 11.

[0049] When the R cam plate 25R and the L cam plate 25L are moved in theforward direction of the disc player 10, the shaft of the loading roller41 is downwardly moved along the cam groove 26A of the R cam plate 25R,the loading roller 41 is separated from the disc 1 and thedrawing/feeding operation of the disc 1 is stopped. At this time, theloading plate is rotated around a predetermined rotatably-supportingpoint (not shown), and the fitting between the loading plate and aprojection (not shown) of the chassis 17 is released, so that the playermain body 11 is supported in the floating style by the chassis 17.

[0050] As shown in FIGS. 1A and 5A, the positioning unit 14 has a stepplate 54, a disc stopper 55, a G plate and a sensor arm 57, and itcarries out the positioning operation of the disc 1 so that the centerof the center hole 2 of a large-diameter or small-diameter disc 1 (thatis, the center of the disc 1) is coincident with the center of theturntable 19 (FIGS. 5A to 5C).

[0051] Fit pawls 58 are formed at both the right and left sides of thedisc player 10 on the step plate 54. As shown in FIG. 7, the fit pawls58 are formed by bending and erecting them in the process of forming thestep plate 54. As shown in FIGS. 5A to 5C, these fit pawls 58 are fittedin the longitudinal grooves 22 formed in the side wall 21 f the driveplate 18 and the cam grooves 26B of the R cam plate 25 and the L camplate 25L. Accordingly, when the R cam plate 25R and the L cam plate 25Lare moved in the forward and backward directions of the disc player 10,the fit pawls 58 are movable in the vertical direction to the driveplate 18 along the longitudinal grooves 22 of the drive plate 18, thatis, movable upwardly and downwardly.

[0052] The downward movement of the step plate 54 enables avibration-isolation stroke L to be kept between the positioning unit 14and the chassis 17. Further, the upward movement of the step plate 54enables the disc 1 to be moved over the turntable 19 of the drive unit16 and pulled into the player main body 11.

[0053] As shown in FIG. 5A, the disc stopper 55 is formed to be U-shapedin section to accommodate the disc 1 pulled into the player main body11. Further, as shown in FIG. 1A, the disc stopper 55 is fitted to thestep plate 54 so as to be movable in the forward and backward directionsof the disc player 10, and the disc 1 pulled and fed into the playermain body 11 by the loading roller 41 is positioned to a predeterminedposition by the disc stopper 55.

[0054] By the mechanism of the G plate 56 and the sensor arm 57described later, the disc stopper 55 is positioned from the initialposition shown in FIG. 1A to a positioning position shown in FIGS. 2Aand 3A at which the center of the center hole 2 of the disc 1 and thecenter of the turntable 19 are coincident with each other, and aretracting position shown in FIG. 4A at which the stopper is separatedfrom the disc 1 clamped and chucked onto the turntable 19.

[0055] The G plate 56 is rotatably supported by a pin 56A implanted onthe step plate 54, and the disc stopper 55 is secured to one end portionof the G plate 56. An opening 59 is formed at the other end portion ofthe G plate 56, and an A hole 60A and a B hole 60B are formed in theopening 59.

[0056] The sensor arm 57 is rotatably supported on the step plate 54A soas to be slightly movable in the forward and backward directions of thedisc player 10. That is, the pin 54A implanted on the step plate 54 isinserted in an elongated hole 57A formed in the sensor arm 57. An armrod 61 is implanted at the tip portion of the sensor arm 57, and a boss62 is formed at the other end portion. The boss 62 is positioned in theopening 59 of the plate 56. A stop pawl 63 which is engageably fitted ina stop groove 70 of a clamp plate described later is formed in theneighborhood of the arm rod 61 of the sensor arm 57.

[0057] The G plate 56 and the sensor arm 57 are urged in acounterclockwise direction a and in a clockwise direction β respectivelyby a tensile coil spring 56B suspended therebetween.

[0058] When a small-diameter disc 1 (for example, 8 cm CD) is pulledinto the player main body 11, the arm rod 61 may abut against the disc 1in an initial stage in accordance with an insertion position of the disc1. However, even when the arm rod 61 abuts against the disc 1, theabutting of the disc 1 is released in the disc pull-in/centeringprocess. Accordingly, in this case, the stop pawl 63 is engagedly fittedin the stop groove 70 under the state that the boss 62 of the sensor arm57 is fitted in the A hole 60A of the G plate 56, whereby the rotationof the G plate 56 is prevented and the disc stopper 55 is positioned tothe positioning position of the small-diameter disc 1.

[0059] When a large-diameter disc 1 (for example, 12 cm CD) is pulledinto the player main body 11, the disc 1 abuts against the arm rod 61 ofthe sensor arm 57, and the sensor arm 57 is outwardly rotated throughthe pull-in operation of the disc 1, whereby the engagement between theboss 62 of the sensor arm 57 and the A hole 60A of the G plate 56 isreleased. The disc 1 presses the disc stopper 55 in the backwarddirection of the disc player 10 against the tensile force of the tensilecoil spring 56B, whereby the G plate 56 is rotated and the boss 62 ofthe sensor arm 57 moves in the backward direction of the disc player 10in the opening 59 of the G plate 56.

[0060] When the disc 1 moves in the backward direction of the discplayer 10 as described above, the disc 1 is separated from the arm rod61 of the sensor arm 57, whereby the boss 62 of the sensor arm 57 isfitted into the B hole 60B of the G plate 56 by the tensile force of thetensile coil spring 56B. When the disc 1 is further moved in thebackward direction of the disc player 10, the G plate 56 is minutelyrotated against the tensile force of the tensile coil spring 56B, andthe rotating force at this time moves the sensor arm 57 in the forwarddirection of the disc player 10 through the boss 62. At the stage thatthe stop pawl 63 of the sensor arm 57 is hooked to the stop groove 70 ofthe clamp plate 66 during the movement of the sensor arm 57, therotation of the G plate 56 is stopped, and the disc stopper 55 ispositioned to the position at which the large-diameter disc 1 ispositioned.

[0061] Actually, when the G plate 56 is further minutely rotated and thesensor arm 57 is minutely moved in the forward direction of the discplayer 10 by the pull-in operation of the disc 1 from the stage that theboss 62 of the sensor arm 57 is fitted into the B hole 60B, a sensor armpress pawl 64 of the sensor arm 57 presses a trigger rackpress-receiving portion 65 of the trigger rack 30 to minutely move thetrigger rack 30 in the forward direction of the disc player 10, whichmakes it an occasion for the rack 43 of the trigger rack 30 to engagewith the final gear 39.

[0062] As shown in FIGS. 1A and 5A to 5C, the clamper unit 15 has aclamp plate 66, a clamp ring 67 and a clamp spring 68, and clamps thedisc positioned by the positioning unit 14 onto the turntable 19 of thedrive unit 16.

[0063] As shown in FIG. 7, the clamp plate 66 is separated from the stepplate 54 of the positioning unit 14, and fit pawls 69 are disposed atboth the right and left sides of the disc player 10 on the clamp plate66 as in the case of the step plate 54. The fit pawls 69 are formed bybending and erecting them when the clamp plate 66 is formed from a metalplate. As shown in FIGS. 5A to 5C, the fit pawls 69 are fitted in thelongitudinal grooves 22 in the side wall 21 of the drive plate 18 andthe cam grooves 26C of the R cam plate 25R and the L cam plate 25L (seeFIGS. 8A and 8B). Accordingly, when the R cam plate 25 and the L camplate 25L are moved in the forward and backward directions of the discplayer 10, the fit pawls 69 are movable in the vertical direction to thedrive plate 18 along the longitudinal grooves 22 of the drive plate 18,that is, movable upwardly and downwardly.

[0064] The upward and downward movement of the clamp plate 66 is carriedout in synchronism with the upward and downward movement of the stepplate 54 of the positioning unit 14, however, the stroke thereof is setto a stroke M larger than the upward/downward movement stroke of thestep plate 54 (that is, the vibration-isolation stroke L). For example,the upward/downward movement stroke of the step plate 54 is set to 2.5mm, and the upward/downward movement stroke of the clamp plate 66 is setto 4.5 mm.

[0065] The stroke M of the clamp plate 66 is set on the basis of thefollowing standard. That is, the disc 1 can be moved over the turntable19 of the drive unit 16 and pulled into the drive unit 16 at theuppermost position of the clamp plate 66 (FIG. 5A). Further, thevibration-isolation stroke can be sufficiently kept between the clamperunit 15 and the chassis 17 at the lowermost position of the clamp plate66 (FIG. 5C), and when the clamp ring 67 clamps the disc 1 on theturntable 19, a clearance T is set between the clamp ring 67 and theclamp plate 66.

[0066] The clamp ring 67 is disposed so as to be freely rotatablerelatively to the clamp plate 66, and pressed against the clamp plate 66by the spring force of the clamp spring 68. However, when the clampplate 66 is downwardly moved to the lowermost position and clamps thedisc 1 onto the turntable 19, it is separated from the clamp plate 66and the clearance T is provided as described above. At the time when thedisc 1 is clamped by the clamping ring 67, the spring force of the clampspring 68 and the attractive force of a magnet 71 installed in theturntable 19 act on the clamp ring 67, and the disc 1 is clamped ontothe turntable 19 by these forces.

[0067] Next, the operation of the disc player 10 thus constructed untilthe recording/reproducing operation is carried out will be described inthe following items (1) to (4).

[0068] (1) As shown in FIG. 1A, when the disc 1 is inserted and the discsensor 24 detects the disc 1, the loading motor 28 is actuated to rotatethe loading roller 41, and the disc 1 is pulled and fed into the playermain body 11. At this time, the disc stopper 55 is located at theinitial position.

[0069] (2) The disc 1 pulled into the player main body 11 abuts againstthe disc stopper 55 and moves horizontally in the forward and backwarddirections. At this time, when the disc 1 is a large-diameter 12 cm CD,the sensor arm 57 is rotated, and the boss 62 of the sensor arm 57 isdetached from the A hole 60A of the G plate 56, and the disc stopper 55is movable to the positioning position for the 12 cm CD.

[0070] As shown in FIG. 2A, when the disc stopper 55 is moved to thepositioning position for the 12 cm CD, the disc 1 is separated from thearm rod 61 of the sensor arm 57, and the sensor arm 57 is rotated in theclockwise direction β by the tensile force of the spring 56B, and theboss 62 of the sensor arm 57 is fitted into the B hole 60B of the Gplate 56. When the disc 1 is further pulled in by the loading roller 41,the sensor arm 57 is horizontally moved in the forward direction of thedisc player 10 until the stop pawl 63 of the sensor arm 57 is engagedlyfitted in the stop groove 70 of the clamp plate 66. At this time, thedisc stopper 55 is positioned to the positioning position.

[0071] (3) As shown in FIG. 9A, the sensor arm 57 is moved forwardly asdescribed above, whereby the sensor arm press pawl 64 of the sensor arm57 (FIG. 2A) presses the trigger rack press-receiving portion 65 of thetrigger rack 30 (FIG. 2B), and the trigger rack 30 is forwardly movedagainst the urging force of the tensile coil spring 30A, so that therack 43 of the trigger rack 30 is engaged with the final gear 39.

[0072] As shown in FIGS. 3A and 3B and FIG. 9B, when the rack 43 of thetrigger rack 30 and the final gear 39 are engaged with each other, thetrigger rack 30 is further horizontally moved in the forward directionof the disc player 10 with the assistance of the driving force of theloading motor 28, and the lock pin 44 of the S arm stopper is separatedfrom the second hole 52 of the key-shaped hole 48 to release the lockoperation of the lock mechanism 47. At this time, the S arm stopper 40is rotated and enters the locus of the moved sensor arm 57 to preventthe sensor arm 57 from returning.

[0073] As shown in FIG. 9C, when the trigger rack 30 goes ahead and therack 43 of the trigger rack 30 and the rack 45 of the R cam plate 25Rare coincident in phase with each other, the trigger groove 42 of thetrigger rack 30 further presses the driving piece 66 through the lockpin 44 and the elongated hole 49, and the rack 45 is engaged with thefinal gear 39 while the rack 43 and the rack 45 are coincident in phasewith each other, so that the R cam plate 25R is horizontally moved inthe forward direction of the disc player 10 together with the triggerrack 30. The horizontal movement of the R cam plate 25R is transferredto the L cam plate 25L by the clamp shaft 27 and the loading plate shownin FIGS. 5A to 5C and FIGS. 8A and 8B, and the R cam plate 25R and the Lcam plate 25L are horizontally moved in synchronism with each other.

[0074] As shown in FIG. 5B, when the R cam plate 25R and the L cam plate25L are moved in the forward direction of the disc player 10 the stopplate 54 and the clamp plate 66 are downwardly moved by the action ofthe cam grooves 26B and 26C of the R cam plate 25R and the L cam plate25L. Likewise, a loading arm (not shown) is rotated by the action of thecam groove 26A, and the loading roller 41 is separated from the disc 1.

[0075] As shown in FIG. 5C, when the step plate 54 and the clamp plate66 are downwardly moved to the lowermost position, the clamp ring 67clamps the disc 1 onto the turntable 19 by the urging force of the clampspring 68 and the attractive force of the magnet 71. AS described above,the disc stopper 55 is also positioned to the positioning position whenthe clamp ring 67 clamps the disc 1 onto the turntable 19.

[0076] (4) When the step plate 54 and the clamp plate 66 are downwardlymoved to the lowermost position, the engagement between the stop pawl ofthe sensor arm 57 and the stop groove 70 of the clamp plate 66 shown inFIG. 3A is released.

[0077] As shown in FIGS. 4A and 9D, the rotating force of the loadingmotor 28 is transferred to the R cam plate 25R through the final gear 39and the rack 45 of the R cam plate 25R to move the R cam plate 25R andthe L cam plate 25L in the forward direction of the disc player 10. Thelock pin 44 presses the S arm stopper 40 in the neighborhood of thefront-limit position of the R cam plate 25R, and moves the S arm stopperin the forward direction of the disc player 10.

[0078] Accordingly, the S arm stopper press portion 72 of the S armstopper 40 shown in FIG. 4B presses the sensor arm press-receivingportion 73 of the sensor arm 57 in the forward direction of the discplayer 10. At this time, the stop pawl 63 of the sensor arm 57 isdetached from the stop groove 70 of the clamp plate 66, so that thesensor arm 57 is minutely moved in the forward direction of the discplayer 10 to rotate the G plate 56, and the disc stopper 55 is forcedlyseparated from the disc 1. As a result, the disc 1 is rotatable withoutcoming into contact with the disc stopper 55.

[0079] In the item (2) of the operation of the disc player 1 describedabove, when the disc 1 is a small-diameter 8 cm-CD, the boss 62 of thesensor arm 57 is engagedly fitted and kept in the A hole 60A of the Gplate 56. Under this state, the small-diameter disc 1 is pulled in bythe loading roller 41, and the sensor arm 57 is horizontally moved inthe forward direction of the disc player 10 until the stop pawl 63 ofthe sensor arm 57 is engagedly fitted in the stop groove 70 of the clampplate 66, whereby the disc stopper 55 is located at the positioningposition. The subsequent operation is the same as the items (3) and (4)of the operation.

[0080] According to the above-described embodiment, the followingeffects (1) to (3) are achieved.

[0081] (1) Since the step plate 54 and the clamp plate 66 are designedso as to be movable vertically to the drive plate 18 (downwardly andupwardly movable), the moving amount of the step plate 54 and the clampplate 66 can be reduced less than when the clamper for clamping the disconto the turntable is moved relatively to the turntable by the rotationof the clamp arm, or when the step plate 54 and the clamp plate 66 areintegrally rotated, so that the disc player 10 can be designed in a thinstructure.

[0082] (2) Since the step plate 54 and the clamp plate 66 are separatelyprovided from each other, the moving amounts of the step plate 54 andthe clamp plate 66 can be set to different values. That is, the stepplate 54 can be set to such a moving amount that the vibration-isolationstroke L can be kept, and the clamp plate 66 can keep thevibration-isolation stroke L, and also can be set to such a movingamount that the clearance between the clamp plate 66 and the clamp ring67 can be kept.

[0083] (3) The fit members which are provided to the step plate 54 andthe clamp plate 66 and can be engageably fitted into the cam grooves 26of the R cam plate 25R and the L cam plate 25L are the fit pawls 58, 69which are integrally formed by bending and erecting them in the processof forming the clamp plate 66, so that the construction of the stepplate 54 and the clamp plate 66 can be more simplified as compared withthe case where the fit members are constructed by caulking pins, andthus the construction of the disc player 10 can be more simplified.

Industrial Utility

[0084] As described above, according to the present invention, thepositioning unit for positioning the disc and the clamp unit forperforming the clamp operation on the disc positioned by the positioningunit are separately provided, so that the present invention can beapplied to not only a reproduction-only disc player, but also a discplayer which can record and reproduce information.

What is claimed is:
 1. A disc player comprising: a positioning unit forpositioning a disc; a clamper unit for performing a clamp operation onthe disc positioned by said positioning unit; and a drive unit that hasa pickup and a turntable, and rotates the disc clamped on the turntableby said clamp unit to take out information from the disc by said pickup,wherein said positioning unit and said clamper unit are providedseparately from each other and movable substantially vertically to saiddrive unit.
 2. The disc player as claimed in claim 1, wherein a stepplate equipped to said positioning unit and a clamp plate equipped tosaid clamper unit are engaged with a cam groove of a cam plate movablein parallel to a drive plate equipped to said drive unit, and movablevertically to said drive plate by movement of said cam plate.
 3. Thedisc player as claimed in claim 2, wherein said step plate and saidclamp plate are moved in synchronism with each other and vertically tosaid drive plate by the movement of said cam plate.
 4. The disc playeras claimed in claim 2 or 3, wherein fit members which are provided tosaid step plate and said clamp plate and engaged with said cam groovesof said cam plate are fit pawls that are integrally formed by bendingand erecting.
 5. The disc player as claimed in any one of claims 2 to 4,wherein said fit pawls of said step plate and said clamp plate areintegrally formed by bending and erecting in a forming process thereof.6. The disc player as claimed in any one of claims 1 to 5, wherein saidpositioning unit is designed so as to position plural kinds of discsthat are different in size.
 7. The disc player as claimed in any one ofclaims 1 to 6, wherein said positioning unit has a step plate, a G platewhich is freely rotatably provided to said step plate and has, at oneend thereof, a disc stopper on which a disc can be supported, and asensor arm having, at one end thereof, an arm rod that can be fitted tothe disc, the fitting positions of the other ends of said G plate andsaid sensor arm being changeable in accordance with plural discsdifferent in diameter so that the discs can be positioned.
 8. The discplayer as claimed in any one of claims 1 to 7, wherein the movingamounts of said positioning unit and said clamper unit are set todifferent values.
 9. The disc player as claimed in claim 8, wherein themoving amount of said clamper unit is set to a value larger than that ofsaid positioning unit.
 10. The disc player as claimed in claim 8 or 9,wherein the moving amount of said positioning unit is set so that avibration-isolation stroke can be kept, and the moving amount of saidclamper unit is set so that the vibration-isolation stroke can be keptand the clearance between said clamper unit and said clamper ring forclamping said disc onto said turntable can be kept.